munlockall.2 (2010 09)

m
munlockall(2) munlockall(2)
NAME
munlockall() - unlock the entire virtual address space of a process
SYNOPSIS
#include <sys/mman.h>
int munlockall();
DESCRIPTION
The munlockall() system call allows the calling process to unlock any portions of its virtual address
space that have previously been locked into memory with
mlock() or mlockall(), including any por-
tions locked due to the
MCL_FUTURE option of
mlockall(). Upon successful completion of the mun-
lockall(), all pages within the process virtual address space are subject to routine paging and/or
swapping and the MCL_FUTURE option will no longer be in effect for the process.
Regardless of how many times a process locks a page, a single
munlockall() will unlock it. When
memory is shared by multiple processes and mlocks are applied to the same physical page by multiple
processes, a page remains locked until the last lock is removed from that page.
The effective user ID of the calling process must be a user with the
MLOCK privilege.
Although
plock() and the mlock() family of functions may be used together in an application, each
may affect the other in unexpected ways. This practice is not recommended.
Security Restrictions
Some or all of the actions associated with this system call require the
MLOCK privilege. Processes owned
by the superuser have this privilege. Processes owned by other users may have this privilege, depending
on system configuration. See privileges (5) for more information about privileged access on systems that
support fine-grained privileges.
RETURN VALUE
munlockall() returns the following values:
0 Successful completion.
-1 Failure. The requested operation is not performed. errno is set to indicate the error.
ERRORS
If
munlockall() fails, errno is set to the following value:
[EPERM] The effective user ID of the calling process is not a user with the
MLOCK privilege.
EXAMPLES
The following call to
munlockall() unlocks the process virtual address space:
munlockall();
SEE ALSO
setprivgrp(1M), getprivgrp(2), mlock(2), mlockall(2), munlock(2), plock(2), privileges(5).
STANDARDS CONFORMANCE
munlockall(): POSIX Realtime Extensions, IEEE Std 1003.1b
HP-UX 11i Version 3: September 2010 − 1 − Hewlett-Packard Company 1